For the Crust:
Add the cubed butter, sugar, salt and vanilla to a stand mixer fitted with a paddle attachment. Mix for about 2 minutes or until it's homogeneous.
Add the egg yolks and mixed until combined.
Add the flour and mix until shaggy, about 45 seconds.
DIVIDE into 2-3 equal pieces and press each into a flat disk. Roll out to a thickness of 3mm, 1/8 inch, in between two sheets of lightly floured parchment paper. Chill for at least an hour.
Peel off the layers of paper and cut your tart bottoms out. Cut a strip for the side. Place the strip for the side in your tart ring. Press the side into the ring and trim the excess.Trim the top so it's flush to the ring.
Freeze tarts for at least half an hour. Bake at 325F for about 12-15 minutes or until just golden. If you're using a traditional tart mold you can just cut the rounds out and press into the form.
For the Cream:
In a medium saucepan, heat the milk and vanilla bean to a boil over medium heat. Immediately turn off the heat and set aside to infuse for 15 minutes.
In a bowl, whisk the egg yolks and sugar until light and fluffy.
Add the cornstarch and whisk vigorously until no lumps remain. Whisk in 1/4 cup of the hot milk mixture until incorporated.
Whisk in the remaining hot milk mixture, reserving the saucepan. Pour the mixture through a strainer back into the saucepan. Cook over medium-high heat, whisking constantly, until thickened and slowly boiling. Remove from the heat and stir in the butter.
Let cool slightly. Cover with plastic wrap, lightly pressing the plastic against the surface to prevent a skin from forming.
Chill at least 2 hours or until ready to serve.
Set oven to 200F.
Add egg whites to stand mixer with whisk attachment, on medium high speed.
Add the cream or tartar and salt to the bowl then begin mixing on low and gradually increase the speed to high.
Once the egg whites have frothed up, gradually add in sugar, 1 tablespoon at a time, whisking until thick, still peaks form.
Add your orange blossom extract and food gel, continue mixing until well incorporated.
Pipe your meringues onto a parchment lined baking sheet, allowing at least an inch of space between each for airflow.
Place on the center rack to bake at 200 for about an hour then turn the oven off and keep closed for an additional 1-2 hours. The meringue cookies are done when they are dried throughout.
Assembly: Fill piping bag with pastry cream, pipe into tart shell. If desired, sprinkle crushed pistachios on top of cream. Place Orange Blossom Meringues on top, drizzle with honey if desired. Serve cold.